Question

Metoda przeciwnych współczynników

{2x-y=4
{ 5x-7y=3


{5x-7y=3
{2x-3y=7

Answer 1

2x-y=4 /*(-7)
5x-7y=3

-14x+7y=-28
5x-7y=3
-------------- dodaj
9x=-25
x=-25/9
x=-2 7/9

2x-y=4
2x-4=y
2*(-2 7/9)-4=y
y=-86/9
y=-9 5/9
--------------------
{5x-7y=3 /*2
{2x-3y=7 /*(-5)

10x-14y=6
-10x+15y=-35
---------------- dodajemy
y=-29

2x-3y=7
2x=7+3y
x=7/2+3/2y
x=7/2+3/2*(-29)
x=-40